angular-docs-cn/packages/language-service/test/reflector_host_spec.ts

81 lines
3.1 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import * as path from 'path';
import * as ts from 'typescript';
import {ReflectorHost} from '../src/reflector_host';
import {TypeScriptServiceHost} from '../src/typescript_host';
import {MockTypescriptHost} from './test_utils';
describe('reflector_host_spec', () => {
// Regression #21811
it('should be able to find angular under windows', () => {
const originalJoin = path.join;
const originalPosixJoin = path.posix.join;
const mockHost =
new MockTypescriptHost(['/app/main.ts', '/app/parsing-cases.ts'], 'node_modules', {
...path,
join: (...args: string[]) => originalJoin.apply(path, args),
posix:
{...path.posix, join: (...args: string[]) => originalPosixJoin.apply(path, args)}
});
const reflectorHost = new ReflectorHost(() => undefined as any, mockHost);
if (process.platform !== 'win32') {
// If we call this in Windows it will cause a 'Maximum call stack size exceeded error'
// Because we are spying on the same function that we are call faking
spyOn(path, 'join').and.callFake((...args: string[]) => { return path.win32.join(...args); });
}
const result = reflectorHost.moduleNameToFileName('@angular/core');
expect(result).not.toBeNull('could not find @angular/core using path.win32');
});
it('should use module resolution cache', () => {
const mockHost = new MockTypescriptHost(['/app/main.ts']);
// TypeScript relies on `ModuleResolutionHost.fileExists()` to perform
// module resolution, so spy on this method to determine how many times
// it's called.
const spy = spyOn(mockHost, 'fileExists').and.callThrough();
const tsLS = ts.createLanguageService(mockHost);
// First count is zero due to lazy instantiation of the StaticReflector
// and MetadataResolver.
const ngLSHost = new TypeScriptServiceHost(mockHost, tsLS);
const firstCount = spy.calls.count();
expect(firstCount).toBe(0);
spy.calls.reset();
// Second count is due to resolution of the Tour of Heroes (toh) project.
// This resolves all Angular directives in the project.
ngLSHost.getAnalyzedModules();
const secondCount = spy.calls.count();
expect(secondCount).toBeGreaterThan(700);
expect(secondCount).toBeLessThan(800);
spy.calls.reset();
// Third count is due to recompution after the program changes.
mockHost.addCode(''); // this will mark project as dirty
ngLSHost.getAnalyzedModules();
const thirdCount = spy.calls.count();
expect(thirdCount).toBeGreaterThan(0);
expect(thirdCount).toBeLessThan(10);
// Summary
// | | First Count | Second Count | Third Count |
// |---------------|-------------|--------------|-------------|
// | Without Cache | 2581 | 6291 | 257 |
// | With Cache | 26 | 550 | 84 |
// | Improvement | ~100x | ~10x | ~3x |
});
});